I have a pair of headers that I am about to put on my '69 mustang. But I was told today by a respectable mustang guy that unless I was going in to race my car, headers would be unnecessary. He said in the long run the amount of power they add to the car will not be worth all the pain that they will cause me. He said that after a while I will constantly have to deal with exhaust leaks from them. I was just wondering what you guys thought. How much extra power do headers give an engine? Would it be better to skip the headers and just put on dual exhaust? ( I was planning to put on the dual exhaust the same time as the headers). Thanks for the input.
If you were to put on those headers, ITS best to install the dual exhaust at the same time. But headers Do come with their problems. They can be harder to change spark plugs, can burn ignition wires. And to make more power with them you should advance your ignition timing. But to avoid exhaust leaks remember to retighten all the bolts, to heads and at the collectors, most of the time they will losen up after getting the engine warmed up for the first time with the new headers.
In my opinion, they're definitely a worthwhile modification, from the standpoint of additional torque, horsepower, and improved mileage. When you get right down to it, cast exhaust manifolds are just the pits. You should be aware however, that those headers will probably cause you some headaches (particulary getting them put in). Expect to expend some sweat and blood getting the headers in and fitted properly. You may have to make some minor modification to the headers through grinding or dimpling the primary tubes to get enough room to get the bolts installed correctly. In extreme cases, you may have to forgo bolts altogether and use allen headed cap screws instead. With the use of good gaskets, (I like the ductile copper or aluminum ones personally) leaks shouldn't be a problem. After gettting the headers put on and tightened, run the motor for about 30 minutes or so and then go back and retighten the head bolts and collector bolts again. Doing this once is normally all it takes to keep things nice and snug. Leather work gloves are also a good idea at this point since those primaries are going to be hot. Good luck,
John
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'66 candyapple red coupe, 289 4v engine,
390 cfm holley carb, performer manifold,
tri Y headers, T-5 WC tranny, Versailles
9" w/ 3.50 gears and a detroit locker, 4
wheel discs.
Amigo, bolt on is a viscious myth perpetrated by design engineers with a sick sense of humor. What it can normally be taken to mean is that you won't have to fabricate any new parts to the things to fit. Modification of existing stuff is a whole nother story.
John
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'66 candyapple red coupe, 289 4v engine,
390 cfm holley carb, performer manifold,
tri Y headers, T-5 WC tranny, Versailles
9" w/ 3.50 gears and a detroit locker, 4
wheel discs.
Originally posted by jahardy-66 Amigo, bolt on is a viscious myth perpetrated by design engineers with a sick sense of humor. What it can normally be taken to mean is that you won't have to fabricate any new parts to the things to fit. Modification of existing stuff is a whole nother story.
John
well dont forget that our cars are not exactly precise when it comes to dimensions, so some minor mods may be needed. i say go for the headers. you can get copper gaskets and stage 8 bolts to keep the gaskets from leaking. as for the collectors, you can use copper gaskets there also.
The problem installing my headers had more to do with having a suitable lift than having to dimple tubes, etc. There are no dimples on my headers! The only conflict was with a clutch linkage pivot adapter I installed as an aftermarket item. I had to grind a crescent into its bracket to gain tube clearance. Otherwise they bolted on as advertized.
Needed 4' of clearance below the car to install them, meaning you need a lift and can't do it on jackstands.
Rbohm raises a very good point about dimensions, so it's really no suprise that things sometimes don't fit the way they were designed to. Even for the headaches mine caused me during the installation (had to grind 3 primaries for bolt clearance, plus heat and bend clutch linkage to keep it from bottoming out on the collectors; it would have been much easier to dimple the collector but I couldn't make myself do it), they've been entirely worthwhile. When it gets down to it, headers and good exhaust pay great dividends in the grunt dept. without spending a fortune along the way. Just be aware that some things may not go exactly the way you think they should when you go to put them in. Once they're bolted up however, you'll be very happy with the results.
John
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'66 candyapple red coupe, 289 4v engine,
390 cfm holley carb, performer manifold,
tri Y headers, T-5 WC tranny, Versailles
9" w/ 3.50 gears and a detroit locker, 4
wheel discs.
Headers...good or bad? 
